Our working hypothesis is that psoriasis is an autoimmune or immune- mediated disease. The goal of our study is to determine the safety and efficacy of the rh-IL11 in the treatment of psoriasis. The study has the additional scientific goal of determining the relative contribution of both activated (CD25+) CD4+ and CD8+ lymphocytes (as well as subsets of these major T-lymphocyte populations) and cytokines to the pathogenesis of psoriasis. The hypothesis being tested is that psosiasis is a disease mediated by activated T-lymphocytes and that IL-11 will decrease lymphocyte activation and thus improve psoriasis. Patients meeting inclusion criteria will be enrolled into this study. Following enrollment the following will be done: physical examination; photography of skin lesions; psoriasis severity assessment score; biopsy of unaffected and lesional skin; baseline laboratory evaluations, including CBC, fibrogen, serum chemistry, C-reactive protein, beta-HCG (where indicated) and urinalysis; baseline EKG, baseline weight, [optional evaluations] ultrasound imaging of psoriatic plaque and/or lymphocyte subset analysis.